1. Field of the Invention
The invention relates to a method for generating a color match between a target object having numerous different target color values and a source object.
2. Description of the Related Art
When printing on materials, such as paper or textiles, a certain coloring should be obtained generally. For this purpose, certain color values are preselected. The color value is a certain mixing ratio of primary colors. A known system of basic colors is YMCK, i.e., yellow (Y), magenta (M), cyan (C, blue), and key (K, black). However, it has been observed frequently that an observer perceives same color values very differently when the printing conditions differ from one another. Differences may result, for example, from different printing methods. For example, offset printing can cause for the same color value a different appearance than letter press printing or intaglio printing. Under certain circumstances, the reproduction by inkjet printing, which is used, for example, for proofing, i.e., for checking a printer's copy, can result in a different perception as compared to the final print produced later. Even for identical printing methods, differences may occur when the printing is carried out at different times, at different locations, or with different printing inks.
In order to explain the invention, proofing is used as an example in the following. Proofing refers to the checking of the printing data with respect to color and correct contents. The results of printing and of proofing should always be the same with respect to color and with respect to contents. The following explanation is limited, of course, to the matching of colors.
For evaluating correct colors of prints, there are different error standards, in particular, ΔE, ΔE94, and ΔE2000. These error standards quantify spacings in multi-dimensional color spaces. The object is to keep the differences between source color location and target color location, which are calculated with these error standards, as small as possible. In order to achieve this goal, conventionally manual corrections within the method for producing the print are carried out. This requires experienced personnel who “know” how to change the color value in a source object in order to obtain the same color perception as in the target object. However, these methods are very complex. They are also very time-consuming.